In the digital age, the seamless interaction between different software applications is paramount. This is where the concepts of HTTP, Web APIs, and API endpoints come into play, serving as the backbone of communication in the vast landscape of the internet and software applications. Let's delve into these concepts to understand their roles and how they work together to facilitate this communication.
Service protection API limits are enforced based on three facets:
If the only limit was on the number of requests sent by a user, it would be possible to bypass it. The other facets were added to counter these attempts. For example:
Each web server available to your environment will enforce these limits independently. Most environments will have more than one web server. Trial environments are allocated only a single web server. The actual number of web servers that are available to your environment depends on multiple factors that are part of the managed service we provide. One of the factors is how many user licenses you have purchased.
The following table describes the default service protection API limits enforced per web server:
Imagine a scenario: in a freezing cold winter, you are heading to the parking lot for your Tesla car. You are holding a big box and have no hand to take out the phone then choose the commands from the menus to turn on the AC remotely, or open the rear trunk. So you just talk to your Apple watch and tell Siri to command the car easily and promptly. Is it an interesting experience you wanna try? If so, you may follow the below steps to finish your personal control application.
REST (REpresentational State Transfer) refers to a Software Architectural Style that defines the standards for exchanging information between two different systems via the HTTP Protocol. It is the most popular architecture for exchanging data on the World Wide Web.
REST defines 6 different principles for Web Services:
Any API (Application Programming Interface) that follows the above principles is referred to as a REST API. In most cases, REST APIs use XML or JSON, but the REST Architecture doesn’t require anything specific as far as this is concerned. REST does not require any particular format, but it accepts any format that can be used in Content Negotiation.
OData (Open Data Protocol) is a set of best practices for developing and using RESTful APIs. It helps you to focus on your Business Logic while creating RESTful APIs without the need to worry about various ways to define request and response Headers, HTTP Methods, Status Codes, Media Types, URL Conventions, Payload Formats, and more.
OData carries the following specifications:
REST is the most essential component technology of OData. OData 3.0 standards require OData users to follow REST principles. OData rests on HTML technology, which resolves the problem of being REST-based in a way. It supports two Protocols for Data Transfer, the XML-based Atom format and JSON.
OData also has guidance for performing actions like defining reusable procedures, tracking changes, and sending many REST requests.
It provides two models for Data Management which include:
In the next section, we will be discussing OData vs REST APIs to know how the two compare in different core areas.
OData vs REST APIs: What’s the Difference?
Let’s now discuss how OData and REST APIs compare to each other:
REST is an architecture that defines how to send messages between a Client and a Server via HTTP. It is a model that states that you can use HTTP and its verbs to perform CRUD Operations (Create, Read, Update, Delete) on the resources exposed by your Services. Thus, REST is more concerned about the architecture.
OData is a standard from Microsoft that relies on the REST Architecture to send specific types of messages over HTTP. It defines metadata in CSDL (Common Schema Definition Language) format to describe the Entity types supported by your Service and their Properties, Data types, and more. Thus, OData is more concerned about the content.
REST defines 6 principles, as has been listed above, to ensure the creation of efficient Web Services and REST APIs must follow these principles. These principles ensure the success of REST Projects.
OData is built on top of the REST Framework, thus, it depends on REST principles. Note that even though OData recommends its users to follow REST principles every time, the requirement can be relaxed in the case of a good reason. A very basic, Compliant Service should be easy to build, with additional work necessary only to support additional capabilities.
REST is used when there is a need to interact with a Data Source, for example, to retrieve data for all Products. It is easier and faster to parse data using REST APIs. It uses URI to expose the Business Logic.
The following operations are available on HTTP:
OData is best used to expose Services and APIs to Systems and Applications. It has facilities for extension to achieve the custom needs of the REST APIs.
Data transfer format is an important factor to consider when comparing OData vs REST. REST supports the transfer of data in any format. Although most REST APIs use XML and JSON formats, REST is not specific in regard to this.
OData specifies that the data should be transferred in either JSON, XML, or Atom format.
Those were the major differences between OData vs REST.
This blog discussed fine differences across OData vs REST APIs. We also discussed concepts behind OData and REST APIs, their specifications and principles.
For Businesses, extracting complex data from a diverse set of Data Sources such as REST APIs can be a challenging task. This is where Hevo saves the day by providing an efficient, reliable and fast ETL Service.
Business Central supports three types of web services: API, SOAP, and OData.
https://www.c-sharpcorner.com/article/creating-html-web-resource-to-show-image-attached-in-notes-using-web-api/
Some time back, I wrote a post for retrieving an image attached to notes using OData, as now for Dynamics 365 CE, we use Web API. So, I am going to share how we can do it using Web API.
Microsoft Dynamics CRM stores all the notes and attachments in annotation entities. Most out of the box entities used to have a relationship with this entity, but while creating our custom entity we can specifically select if we want to associate our custom entity with notes or not use the following option under Communication & Collaboration. Keep in mind once you enable this option, there is no way to disable this option, but if you are not sure, if you need notes or not at the time of your entity creation it's better to leave this option un-selected, so that you can select this option after sometime if required.
Note
The default size for notes attachment is 5 MB but if required, you can increase this limit to up to 32 MB.
Get entity image from notes
Similar to earlier versions we can upload the image to notes in Dynamics 365 CE.
Once image is attached to notes, we can retrieve it using Web API retrievemultiple request where we can query notes based on ObjectId field, we need to pass entity id field for objectid field in notes. We can using following code, in our html webresource,
Create and deploy html web resource
Now, we need to create an HTML web resource and use the above code under Text Editor.
After that, we can put this web resource to our required Entity Form and we should be able to see the first attached image in web resource after refreshing the page.
Next we will explain how to create a HTML web resource and use our JavaScript method to get and display the image. We need to implement the following two steps:
· Create HTML page
· Deploy HTML page and SDK.REST.js using web resource
Create HTML page
Create a HTML page using a HTML editor. Use the following code for the HTML page:
Deploy HTML page and SDK.REST library using web resource
Use following procedure to deploy a HTML page and SDK.REST library in Microsoft CRM.
Note: Please refer to my previous article for the SDK.REST.js location.
Now we can place our HTML web resource in the account entity form by navigating to Insert -> Web Resource options. Save your changes and then publish the account entity form.
